I've caught a lot of flack (imagine that) about using CGI.
The main reason is that CGI has the overhead of loading & unloading the Python interpreter on every request. The other methods load the Python interpreter once (or a small, fixed-number of times), then handle lots of requests from that process (or pool of processes), and then optionally unload if server-load drops.
However CGI is old and fairly entrenched, so it's easy to find with cheap hosting services -- what do they care if your site is slow?
I understand there are several other options, to wit: mod_python, fastcgi and wcgi. I've messed around with mod_python without luck. What are your suggestions?
Generally, one writes to a framework (Django[1], web.py[2], TurboGears[3], CherryPy[4], etc) that either has a preferred/suggested method of interface, or allows you to plug into [m]any of the items you list. I know Django is happy with mod_python and wsgi (and I suspect fastcgi, but I'll let you google that). YMMV with the others. I've even seen an abomination of a hack that ran Django under CGI (whooooie, is the performance bad!). I think the general direction of the Python web-world seems to be moving toward WSGI (and Graham Dumpleton's work on mod_wsgi[5]; IIUC, he was heavily involved in the initial mod_python) instead of mod_python.
Since you seem fairly adamant about *not* using a framework and cobbling together the universe from the ground up, you might look into Paul Boddie's "WebStack"[6] which abstracts away a number of the main interfaces into a common interface. Kindly, his work even allows you to plug into a CGI interface since that's what you're familiar with, and then shift to a different interface.
-tkc [1] http://djangoproject.com [2] http://turbogears.org [3] http://webpy.org [4] http://www.cherrypy.org [5] http://code.google.com/p/modwsgi/ [6] http://www.boddie.org.uk/python/WebStack.html -- http://mail.python.org/mailman/listinfo/python-list
